Hedge trimmer



Dc. 30, 1941. 1 s,Y M|SCHKER 2,268,221`

HEDGE TRIMMER Filed April 14, 1941v zo 38 Inventur' Patented Dec. 30, `1941 ,UN I TE D STATES PAT E N T O FFI CE HEDGE TRVIMMER John S. Mischker, Milwaukee, Wis.

Application April 14, 1941, Serial N o. 388,478 s claims. (c1. :io-22s)` This invention appertains to hedge trimmers, and more particularly to `a motor-driven hedge trimmer of the type employing a reciprocating toothed blade.

One of the primary objects of my invention is to provide a compact and durable device. which caribe manufactured and placed upon the market lat a reasonable cost, `and which will effectively accomplish the expeditious trimming of hedges.

Another salient object of my invention is to provide novel means for supporting and mounting `the blades relative to one another, so that friction between the parts will be reduced to a minimum, and whereby overheating of the parts will be prevented.

A further object of my invention is to provide a motor-driven hedge trimmer in which an electric motor of the ordinary type now found in the open market can be employed, and easily connected to the device to form a directpartthereof.

Astill further object of my invention is to provide a manipulating handle for the hedge trimmer connected to the motor and the gear casing for the drive, whereby the device will be thoroughly braced to form a strong, rigid structure.

With these and other objects in view, the invention consists in the novel construction, arrangement, and formation of parts, as will be hereinafter more specifically described, claimed, and' illustrated in the accompanying drawing, in which:

Figure 1 is a side, elevational view of my improved device, parts of the view being shown broken away and in section to illustrate` structuraldetail;

Figure 2 is a top plan `view of my improved hedge trimmer, with parts thereof broken away and in section;

Figure 3 ls a bottom plan view of my hedge trimmer withparts thereof broken away and in section;

Figure 4 is an enlarged, transverse sectional view through the hedge trimmer, taken on the line 4-4 of Figure 1 looking in the direction of the arrows, showing a preferred type of driving mechanism for the reciprocating blade;

`Figure 5 is a rear end elevational view of the hedge trimmer, the view being taken substantially on the same scale as Figures l, 2 and 3; f Figure 6 is a transverse,V sectional view through the cutting mechanism, taken on the `line 6--6 of Figure 1 looking in the directionof the arrows;

and

Referring to the drawing in detail, wherein` similar reference characters indicate`corresponding parts through the several views, the letter H generally indicates my improved `hedge trimmer, and the same includes a gear casing I0 which` functions to support the various parts of my apparatus. One side of thegear casing I0 is left open to permit access to be had to the interior thereof, and this open side can be closed by a removable cover plate II.

By referring to Figures 1 and 4, it can be seen that the gear casing embodies a top wall I2, a bottom Wall '|3, a 'side wall` I4, rear'wall I5, and a front wall I6. The rear `wall I5 has formed thereon and projecting outwardly therefrom, a`

transversely curved bracket arm I1, which forms a seat for the electric motor I8. The motor I8 can `be rigidly fastened to `the bracket arm by screws I9.

The front of the casing forthe motor is adapti In order to brace the entire structure andfacil-` itate the manipulation of the trimmer, I provide a special Vform of handle 22.. This handle 22 is of a U-shape, and extends from the outer end of the motor to the extreme front end of the gear casing. The rear end of the lhandle 22 has formed thereon attaching feet 23 to permit the easy connection of the handle to the casing of the` motor by screws. The front end of the handle extends down toward and over the forward front wall of the gear casing, and has formed l thereon a at attaching foot 24 for engaging the front wall of the gear casing, and, hence,` the handle can be easily connected to the gear casing by the use of fastening elements. such as screws.

As the handle 22 connects the motor and gear casing together, the same forms` an effective brace for rigidly uniting-these parts.

Projecting forwardly fromlthe gear casing is.

an elongated, longitudinally extenrlggsuppurtv'ing yandgu'ardfpie'ce 25 for the .stationary gc'utting `bladeY 26 and the reciprocatingcuttingblade 21. f. The .support and guardv for l,the blades can-bel made of sheet metal suitably fabricated or j folded `to. provide va :dat bottom. wall 23, atop wall 29 v.wall-30. y The,..forward edge' of .down to provide a guard flange 3|, which termiand a' connecting, longitudinallyextending side `the top wall is turned nates' over and in slightly spacedbrelation to the a reciprocating top blade 21. The bottom wall 28 extends slightly beyond the .flange 3l, and `the bottom stationary blade 26 fits directly upon the inner surface of the walll 28, and is firmly and To reduce friction, the upperface of the 'top reciprocating blade 21 has secured thereto at' spaced points bearing blocks 33, which are received within the guide' and support 25, as can be clearly seen by referring to Figures 2 and '1. These bearing blocks engage the top-wall 231 of the guide and support 25 and the side wall and flange 30 and 3| thereof.

The lower ,end of` the front wall I6 of the gear casing is provided with a forwardly projecting attaching arm 34, and this arm is rigidly fastened to the guide and sup'port 25 by means of a screw 35.` This lscrew extends throughthe arm 34, the top. Wall of the guide and support 25, and into a nut and spacer 36 disposed in the guide and support 25.

7 The rear ends of the blades 26 and 21 extend vgear casing by spaced screws 38, which extend into the lower wall of the gear casing through the lowerwallof the guide and support 25, and said stationaryblade 25. The lower edge of the cover plate Il of the gear casing I has also formed thereon an inturned flange Il', which extends under and engages the stationary blade 26.

The blades 26 and 21 have formed thereon a plurality of V-shaped cutting teeth 39, and these teeth project laterally from the blades at one side of the guide and support 25. The teeth 39 for the stationary blade 26 have their sharpened side edges notched as at 40, to catch the branches of the hedge being trimmed, and to prevent the branches from slipping Vvout between the teeth during the cutting operation.

Attention is called to Figures 2 and 3, and it will be noted that the outer end of the blade 26 has formed thereon a notched cutting spur 4I, while the forward end ofthe blade 21 is provided with a cutting edge 42, and relatively heavy branches can easily be cut between the cutting barb 4I and the edge 42.

Obviously, under certain conditions as a substitute for the relative reciprocating end spurs 4I and 42, I may attach an independent crank blade to the spur 4I and connect the `sameto the reciprocated spur 42 or cutting blade, whereby the reciprocating blade and associated spur will operate similar to a pair of shears.

The driving mechanism for the movable blade 2.1 includes the swinging lever 43 rockably mounteid-at its upper end upon a pivoted stud 44 car- 75 f aaeaaei ried by the gear casing. The lower end of the j swinging or oscillating lever 43 has formed thereon or secured thereto a drive pin 45, which is received in the bearing knuckle 31 carried by the inner end of the movable blade.

Intermediate the ends of the lever, a slot 46 is formed which receives the eccentric drive pin 41 carried by the Worm wheel 48, which meshes with the worm 2| on the armature shaft of the motor.

'I'he worm wheel 4B is suitably mounted upon a supporting shaft 49 mounted in a bearing 50 formed on the gear casing Ill. Y

From the foregoing description, it can be seen that when the electric circuit is closed through ther motor I3, the lever 43 will be swung back and forth, and this will impart the desired rapid movement to the movable reciprocating blade 21.

Great stress is laid upon the simplicity of my hedge trimmer andthe novel means employed for mounting and guiding the plates on the gear casing.

Changes in details may be made without departing from the spirit or the scope of my invention, but whatl claim as new is:

1. A portable, power-driven hedge trimmer comprising, a gear casing, a motor connected to the gear casing, a manipulating handle connecting the gear casing and motor, a forwardly projecting blade support and guide secured to the gear casing including a bottom wall, a spaced top wall, and a connecting side wall, a depending guide flange formed on the forward edge of the top wall, a stationary cutting blade rigidly secured to the bottom wall, a movable blade mounted upon the stationary blade and extending into the gear casing, means in said gear casing for reciprocating the movable blade from the motor, and spaced bearing and guide blocks rigidly secured to the movable blade and slidably mounted 4o in the guide and blade support, said bearing and guide blocks engaging the top wall, iiange, and

side wall of said guide and blade support.

2. A portable, power-driven hedge trimmer comprising, a gear casing having one side open,

a. removable cover plate for closing said open side. a forwardly projecting attaching arm on said gear casing, a rearwardly projecting supporting bracket on said gear casing, an electric motor rigidly secured to the. bracket andv fitted against 50 the rear wall oi' the gear casing, and including an armature shaft extending into the gear casing, a manipulating handle rigidly secured at its rear end to the rear end of the motor and at its forward end to the front of said gear casing, a guide and blade support rigidly secured to the arm, a stationary blade secured to the guide and blade support, a reciprocating blade mounted upon the stationary blade and carried by said guide and blade support and having its inner end extending into the gear casing, and a drive mechanism in said gear casing operatively connecting the armailirel shaft to the inner end of said reciprocating a e. 3. A portable, power-driven hedge trimmer comprising, a gear casing having one side open, a removable cover plate for closing said open side, a forwardly projecting attaching arm on said gear casing, a rearwardly projecting supporting bracket on said gear casing, an electric motor rigidly secured to the bracket and tted against the rear wall of the gear casing, and including an armature shaft extending into the gear casing= a manipulating handle rigidly secured at its rear end to the rear end of the motor and at its forward end to the front of said gear casing, a

cuide and blade support rigidly secured to the arm, a stationary blade secured tothe guide and blade support. a .reciprocating blademounted upon the stationary blade and carried by said guide and blade support and having its inner end extending into the gear casing, a drive meehanism in said gear casing operatively connecting the armature shaft to the inner end of said rer ciprocating blade, said guide and blade support 

